What is the ruling regarding a woman's prayer and fasting if her menstrual cycle is irregular, and its duration and color vary from month to month, and what is the ruling regarding the hours during which the bleeding temporarily stops?

It should be known that a woman's menstruation may come earlier or later, and its duration and flow may increase or decrease. There is no problem with that, nor with it occurring twice in a month if there are 13 days or more between the two occurrences.

Menstrual blood may begin dark and then lighten in color and decrease. Discolored discharge (kudrah) and yellowish discharge (sufrah) are considered menstruation if they occur during the customary period or if they are continuous with blood. However, after purification (tuhur), they are not considered anything. Purification is recognized by the emission of a white discharge (al-qassah al-bayda') or complete dryness.

If the discolored discharge stops and the cotton comes out clean, then that is purification, and ghusl (ritual bath) and prayer become obligatory. Any discolored or yellowish discharge that appears after that is not considered menstruation unless it is clear blood.

If the cessation of bleeding occurred completely after Dhuhr and the cotton came out clean, but you did not perform ghusl, then you must make up the Dhuhr, Asr, Maghrib, and Isha prayers. However, if the cotton had traces of yellowish or discolored discharge, then you are not required to make up the prayers. Vaginal secretions after purification do not cause harm unless clear blood appears.